As ext4 introduced more reliability than ext3 with block journals, is there any chance to suppose it 100% reliable? What if enabling block journaling on it, which is disabled by default?

I have an embedded linux device, after installation keyboard and monitor is detached and it works standalone.

My duty is to make sure it has reliable file-system so with errors there is no way for manual correct faults on device. I can't force my customer to use a ups with each device to ensure no fault by power-failure.

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1 Answer
1

If you want to minimize chances of data loss in case of a sudden system abort (power failure/kernel panic/whatever), you may try data=journal and sync options. This will kill performance, but reduce risks of data loss.

I think you should better define what you mean by reliability of file system. What you expect from it? Against what failure modes do you want to protect yourself? It may very well be, that using UPSes, reliable redundant hardware and solid software would be better option than tinkering with file system mount options.

my linux system is an embedded system with no monitor or keyboard attached. so i want it to be more reliable in case of power failure, etc ... i know block journaling is a way but i want to know if there is any more option. i can't offer my customer to have a ups for each device.
–
aminMar 7 '11 at 10:11

2

An application can do more than a filesystem here. If you fsync() or fdatasync() at proper times, then chances of loosing user's data are minimal, even without synchronous mount.
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Paweł BrodackiMay 17 '11 at 11:16